A versatile nanocomposite made of Cd/Cu, chlorophyll and PVA matrix utilized for photocatalytic degradation of the hazardous chemicals and pathogens for wastewater treatment

In this work, a novel composition of cadmium sulfide (CdS), copper(II) hydroxide (Cu(OH)₂), copper(II) oxide nanoparticles, and chlorophyll (Chl) is prepared based on polyvinyl alcohol (PVA) matrix. The characterization of the CdS/Cu(OH)₂/CuO@PVA-Chl nanocomposite has been carried out by the various analytical methods. Then, the prepared CdS/Cu(OH)₂/CuO@PVA-Chl is then applied as a very efficient photocatalyst for degradation of the hazardous dyes such as methylene blue (MB), Congo red (CR), and 4-chlorophenol (4-CP) in the aqueous samples. For the preparation of the intended nanocomposite, the Chl has been extracted from fresh spinach via a convenient mechanical adsorption/desorption method. In the obtained optimum conditions, a great degradation efficiency (ca. 97.6%) for the MB dye achieved by simultaneous application of the prepared CdS/Cu(OH)₂/CuO@PVA-Chl photocatalyst and the visible-light (LED 70 W, λ = 425 nm), over a 60 min contact time. Moreover, the degradation efficiency of the CR and 4-CP dyes were ca. 92% and 88%, respectively. The reusability investigations have revealed that no significant loss in the catalytic performance is occurred over seven times recycles. As well, degradation of the pathogens by the CdS/Cu(OH)₂/CuO@PVA-Chl nanocomposite has been screened under the obtained optimal conditions. Briefly, the diameter of the inhibition zones by the prepared composite film has been evaluated to be ca. 11.0 (± 0.1) and 9.0 (± 0.1) mm for S. aureus and E. coli bacterial cells, respectively.